This invention generally relates to the art of electrical connectors and, particularly, to a camming system for mating and unmating a pair of connectors.
Mateable electrical connector assemblies generally include a pair of connectors having respective housings each mounting a plurality of terminals in respective terminal-receiving passages. Each connector housing defines a forward mating end and a rear end thereof. The terminals may be connected to individual wires of a multi-wire cable which extends away from the rear end of the connector. A cover or hood may be provided to enclose the rear end of the connector about the terminated end of the multi-wire cable.
Electrical connectors of the general type described above sometimes include some form of mechanism to assist in mating and unmating the connectors. This often is true with connector assemblies that mount a large number of terminals, and if the resulting mating and unmating forces are relatively large. In addition, such mechanisms often are employed to assure that the connectors are mated generally parallel to a mating axis and to avoid forcing the connectors together in a canted orientation which could damage the connectors and particularly the terminals thereof.
One type of mechanism for assisting in mating and unmating a pair of electrical connectors commonly is called a camming system. Slides and the like, are mounted on one of the connectors for cooperation with mechanisms on the other connector to define a cam track and cam follower arrangement which is effective to draw the connectors into mated condition and to assist in separating the connectors toward an unmated condition.
A camming system of the above described type is disclosed in U.S. Pat. No. 5,660,556 and in German laid open publication DE 196 38 368. According to the teaching of these documents a cam track is defined in a lock slide member slidably held on one of the connectors and a cam follower is formed on the other connector.
However, these and many other similar prior art camming systems rely on lock slide members held slidably in a direction perpendicular to the mating axis and a relative movement in mating direction is caused only between the first and the second connector housing. No relative movement is caused in mating direction between the lock slide member and the said one of the connector housings. Significantly, if space consumption of a connector assembly becomes a critical issue then prior art camming systems and especially the movement of both connectors relative to each other in these prior art arrangements often is not apt to cope with the actual requirements.
The present invention is directed to solving the problems of prior connector camming systems and providing an effective system for assisting in mating and unmating a pair of connectors.
An object, therefore, of the invention is to provide a new and improved mating and unmating camming system for an electrical connector assembly.
In an exemplary embodiment of the invention, the connector assembly includes a first and a second connector each having a housing mounting a plurality of terminals mateable with the terminals of the other connector, and a camming system for moving the housings toward and away from each other along a mating axis to mate and unmate the connectors. A lock slide member mounted on one of the housings includes a cam track and the other housing having a cam follower projecting into the cam track for mating the connectors in response to a sliding movement of the lock slide member. According to the invention mounting means mount the lock slide member on the first connector slidably movable along a path (E) extending transverse in a non-perpendicular direction relative to the mating axis. As a consequence thereof, moving of the lock slide member causes a displacement of the lock slide member relative to the first connector housing in mating and unmating direction adding to the total relative displacement caused by the cam track and cam follower arrangement.
Specifically, in a preferred embodiment of the invention the camming system includes an lock slide member which has at least two cam track and cam follower arrangements and both housings have cam followers projecting into the respective cam track for mating and unmating the connectors in response to a respective sliding movement of the lock slide member. According to this double action movement caused by both of the cam track and cam follower arrangements a smaller angle of inclination is used for each cam track arrangement resulting in reduced friction forces and causing less wear and a higher reliability of the arrangement. Moreover, a reduced angle of inclination further ameliorates the risk of unintended unmating due to vibrational forces or mechanical shocks.
In the preferred embodiment of the invention the lock slide member is a generally u-shaped integrally molded part, having two elongated arms extending in parallel on opposite sides of the one connector housing and defining two pairs of cam tracks in each elongated arm. One of both pairs of cam tracks defines at least two regions having a different angle inclination relative to each other. As a consequence thereof, the movement of both connector housings relative to each other in relation to the sliding movement of the lock slide member is well adapted to forces created by mating and unmating the terminals which ensures a user friendly low mating force operation.
Still further, in the disclosed embodiment, said cam tracks comprise an inwardly projecting rib and said cam followers comprise a distal radially extending rib avoiding a slipping of the cam followers out of the respective cam track.
Preferably, latch means operatively associated between the lock slide member and the one housing to define discrete unmated and mated positions for the lock slide member provide for a fail safe operation, even under the influence of increased vibrational forces or severe mechanical shocks. In detail, preferred latch means comprise an abutment boss abutting in the fully unmated position of the lock slide member a recess of a side wall of the one connector housing and securing the lock slide member in an unmated position.
In a further preferred embodiment, one of the connector housings comprises a terminal carrying element fixedly held on the one connector housing which mounts a first plurality of terminals. A modular terminal carrying insert which mounts a second plurality of terminals is adapted to be inserted into an associated opening of said one of the connector housings. In the mounted position, said terminal carrying modular insert is elastically held in said associated opening of said one connector housing and provides for an elastic lateral displacement relative to the fixedly mounted terminal carrying element during mating and unmating.
In the disclosed further preferred embodiment, said fixedly mounted element is an integral part of said one of the connector housings and carries a first plurality of terminals including a standard set of terminals and said modular element carries a second plurality of terminals comprising a customized set of terminals.
Other objects, features and advantages of the invention will be apparent from the following detailed description taken in connection with the accompanying drawings.